Continuation, improvement, and expansion of the UCSD Nuclear Magnetic Resonance/Mass Spectrometry Research Resource Center is proposed. This Facility which includes 4 nmr spectrometers (Varian HR-220/Nicolet TT-100, JEOL PS/PFT-100/Nicolet 1085, Varian CFT-20, and Hand-Fabricated Broadband/Nicolet 1082) and a gas chromatography/mass spectrometer (LKB-900) has been operating for the last two years. The proposal includes continued operation and upgrading of the existing spectrometers and the additional of a Bruker WH-360 nmr spectrometer for work at very-high field with 31P, 13C and 1H nuclei. Use of the facility would be by individual scientists both at the University of California, San Diego and at other institutions in the vicinity. Additionally, collaborative efforts between some of these users and resource personnel is planned. Importantly, continuation of seven core research projects which depend heavily on nmr and mass spectrometry is planned. One deals with nmr instrument development and application, five with the application of nmr to biochemical problems in the areas of intracellular metabolytes/dehydrogenases, polynucleotides, phospholipases/membrane phospholipids, bacterial cytochromes, and peptides/hormones, and one deals with the use of mass spectrometry in studying diseases resulting from inborn errors in metabolism.